Security – DDoS attack simulation using MININET

First, DON'T capitulate. He is not only an idiot but DANGEROUSLY wrong. In fact, releasing this information would violate the PCI standard (which is what I'm assuming the audit is for since it's a payment processor) along with every other standard out there and just plain common sense. It would also expose your company to all sorts of liabilities.

The next thing I would do is send an email to your boss saying he needs to get corporate counsel involved to determine the legal exposure the company would be facing by proceeding with this action.

This last bit is up to you, but I would contact VISA with this information and get his PCI auditor status pulled.

I don't agree that there isn't anything you can do. There are lots of things you can do and depending on the size of the attack and the size of the hardware you've got you stand a pretty good chance on defending yourself.

For SYN floods google a bit. You probably want a spanking new Linux kernel as there have been quite a few improvements lately. Go for 3.6 and enable syn cookies. There are a couple of other tunables you can tweak. Make sure to read up on it first as randomly tuning stuff is never a good idea and will cause problems.

If is is a HTTP flood, which is common these days you might want to consider Varnish. You might be able to identify the attacking requests by some pattern and kill them off in vcl_recv. You can deploy the shield module in order to kill of these connection as serving up an error page is a wasted effort. Be warned: This is not a quick fix and will require substantial effort on your end.

Good luck.